Crown control

ABSTRACT

This disclosure provides a crown control apparatus for controlling the contour of the roll opening formed by the working rolls of a rolling mill. The upper roll is ultimately supported by one or more roller assemblies consisting of a plurality of axially aligned short-faced rollers. These rollers are rotatably supported on a shaft carried by a separator beam located between the mill housings. The beam includes two opposed projecting arms between which a threaded screw applies a force to deflect the beam relative to the pass line of the mill. This deflection produces a crown on the roller assemblies that is transmitted ultimately to the working rolls.

0 United States Patent [151 3,657,913 Talbot Apr. 25, 1972 s41 CROWN CONTROL 3,147,648 9/1964 Sendzimir ..72/242 3,355,924 12/1967 Sendzimir..... 72/241 [72] Inventor: Howard Hubbell Talbot, Pittsburgh, Pa. 3,429,166 2/1969 Baker let 72/245 [73] Assignee: UnitedP EnbgmeEriSg and Foundry Comy Examiner Lowe A Larson ms urg Attorney-Henry C. Westin [22] Filed: Aug. 29, 1969 [57] ABSTRACT [21] Appl. No.: 854,055 v This disclosure provides a crown control apparatus for con- I trolling the contour of the roll opening, formed by the working [30] Foreign Application Priority Data rolls of a rolling mill. The upper roll is ultimately supported by one or more roller assemblies consisting of a plurality of axi- Sept' 1968 Great i i "46238/68 ally aligned short-faced rollers. These rollers are rotatably supported on a shaft carried by a separator beam located CL 72/242172/237 between the mill housings. The beam includes two opposed 1 s /0 32113 9/ projecting arms between which a threaded screw applies a [58] Field of Search ..72/24l, 242, 2 force to deflect the beam relative to the pass line of the mill. 72/240, 237 This deflection produces a crown on the roller assemblies that r is transmitted ultimately to the working rolls. [561 Rmmces i 8 Claims, 6 Drawing Figures UNITED STATES PATENTS 3,546,914 12/1970 Leifeld et al... ..72/242 7 I @Z l2 5 77-1] 52 65 Q mg.

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v 36 32 29 4 33 36% l I U 35 i 1\\ l a5 PATENTED APR 2 5 m2 SHEET 1 BF 4 INVEN TOR. wnm'o M TALBOT BY ATTORNEK PATENTEDAPR 25 I972 SHEET 8F '4 INVEN TOR HOWARD H. TALBOT 63 C. My ATTORNEY.

CROWN CONTROL This invention relates to a rolling mill provided with roll deflecting means for controlling the crown of the rolling mill rolls.

In order to obtain close gauge tolerances and flatness, modern mills have been provided with a mechanism for applying roll deflecting forces to the rolls in order to control their contours. It will be appreciated that in a rolling mill the rolling loads applied to the center of the roll flexes or bends the rolls between their journals. This flexing, unless compensated for by a machined crown on the rolls, will produce, as a result, a product having a variable thickness across its width.

To alleviate these conditions, there have been employed crown control devices which flex the rolls to counteract for the inherentdeflection caused by the rolling loads. Such devices have been very successfully employed for the backup rolls of four-high mills and includehydrauliccylinders arranged in either of two separate forms. The cylinders were either mounted between the journals of the backup rolls,

whereby'two cylinders provide equal and opposite forces tov bend the rolls, or in the second form the cylinders are mounted on the housings themselves; a cylinder being pro vided for each roll end.

In both of these arrangements, the screwdown screws of the millare subject to the total bending forces in addition to the rolling loads and, in the latter arrangement, the reaction forces of the cylinder are taken by the housing, which substantially adds to the expanseof the mill.

In more recent forms of crown control, reactionforce absorbing means in the form of beams or additional cylinders I have been included in the mill to relieve the mill housings and screws from the roll bending reaction force.

. In the known forms of crown control devices, the backup rolls are necessarily constructed with extended journals on which are mounted outboard bearing chocks for the roll bending device. This construction, along with the hydraulic roll bending cylinders and associated pumps, controls, etc., does represent an additional capital expense that may not be fully' justified in certainrolliug mill installations or embodiments.

It is an object of the present invention to provide a crown control system for the rolls of a rolling mill or like device wherein reaction forces from roll bending cylinders are not imposed upon the housing and screws of the mill.

It is another object of the present invention to provide an apparatus for deflecting a roll support means to control the crown of the working rolls at their bite, which apparatus is more economical and adaptable to existing rolling mills and like processing machines.

h In one form of the present invention there is provided in combination witha cluster-type rolling mill, four-high or sixhigh rolling mills or the like, at least one beam positioned in a rolling force transmitting relation between the mill housing and the ultimate support rollers for the working rolls of the mill and force generating means secured to the beam for imposing a self-contained bending moment on the beam for deflecting the support rollers to control the crown of at least one working roll at the work roll bite.

These features and advantages, as well as others, will be better understood when the following description is read along with the accompanying drawings, of which:

FIG. 1 is an elevational view, partly in section, illustrating a cluster-type rolling mill incorporating the features of the present invention,

FIG. 2 is a sectional view taken along lines II-II of FIG. 1,

FIG. 3 is a plane view of the rolling mill illustrated in FIG. 1,

FIG. 4 is a sectional view taken along lines IV--IV. of FIG. 1

cluster-type rolling mill. As shown in these figures, the rolling mill essentially comprises a pair of spaced-apart housings 11 and 12 which are octagonally shaped and provided with circular windows 13 and 14 which are enclosed by covers 13a and 14a during operation of the mill. Supported by the housings within these windows are a total of 20 rolling mill rolls which i are divided into an upper set of rolls and a lower set of l0 rolls.

With respect to the lower set of rolls, they comprise a small diameter work roll 15 supported in a nested relation by backing rolls l6 and 17 that are, in turn, supported by three driven backing rolls l8, l9 and 21,.Completing the lower set of rolls are four relatively large diameter backup rolls 22, 23, 24, and 25 which have bearing chocks mounted on their ends and supported in the windows 13 and 14. The rolls 23 and 24 have eccentric members 26 and 27 associated with their chocks and form part of an apparatus for rapidly adjusting these rolls, hence, the work roll 15, relative to a material pass line through the mill. Engaging the members 26 and 27 are push-pull bars 28 that have gear teeth in mesh with idle gears 29. Meshing with these idle gears are rack gears 31 that are slidably located in the lower part of the housing and connected to the pistons 32 and 33 received in a cylinder 34. Nuts 35 are threaded on handwheel rotated shafts 36 that form adjustable stops for adjustment of the rolls 23 and 24 in one direction. Adjustment means 37 and 38 are provided for positioning the backup rolls 22 and 25, respectively, relative to the pass line'of the mill and, since these means are similar to other means for adjusting correspondingly located upper support rolls, they will not be described in greater detail.

With reference now to the upper set of rolls, they comprise a small diameter work roll 41 supported in a nested relationship by backing rolls 42 and 43 that are, in turn, supported by three driven backing rolls 44, 45 and 46. Completing the upper set of rolls are four groups of roller assemblies 47, 48, 49 and 50, each consisting of a plurality of spaced-apart shortfaced rollers 51 mounted by antifriction bearings on a shaft 52. As best shown in FIG. 4, each of the roller assemblies 47 and is supported by a housing cross beam 53 secured between the housings by a threaded stud 11a and nuts 11b. The cross beams 53 have a plurality of projections 54 that engage eccentric portions of the shaft 52 at its ends, as well as intermediate each roller 51, which portions are eccentric with and each comprise, as shown in FIG. 1, a spindle 57 7 FIG. Sis an elevational view, partly in section, of a second embodiment illustrating a four-high rolling mill incorporating the features of the present invention, and

FIG. 6 is a sectional view taken along lines VI-Vl of FIG. 5. I

With reference to FIGS. 1, 2, 3 and 4, there is illustrated one embodiment of the present invention in the form of a threadably received at one end in a nut 58 that is bolted to the housings. Gear teeth 59 formed on the other end of the spindle 57 mesh with a gear 61 secured to each end of the associated roller assembly. Rotation of the spindle 57 by a winch or other suitable means attached at end 57a causes the shaft 52 to rotate about its eccentrically mounted portion in the cross beams 53 to produce simultaneous displacement of all the rollers 51 relative to the mill pass line. After the desired position of the roller assemblies is attained, lock nuts 62 prevent further rotation of the spindle 57.

A description will now be given of the crown control feature of the present invention which is best illustrated in FIGS. 2 and 3. The illustrated crown control feature has been incorporated with the roller assemblies 48 and 49, although, as will be apparent to those skilled in the art, it may be incorporated with any one or more of the roller assemblies 47 and 50, as well as the backup rolls 22 23, 24 and 25.

The illustrated crown control apparatus comprises for each roller assembly 48 and 49 a separator beam 63 secured to the housings 11 and 12 by wedges 64. Extending downwardly from the beam are a plurality of projections 65 that engage eccentric portions 52a formed on the shaft 52 at its ends and between the rollers 51. The separator 63 is formed with two opposed arms 66 and 67 that project upward between the housings. Enlarged circular castings 68 and 69 are made part of the projecting ends of the arms 66 and 67, respectively. Opposite hand threads formed in each casting 68 and 69 are engaged by similar threads formed on a shaft 71 that extends beyond the housing 11 and is rotatably mounted thereto by a bearing block 72, but held against axial movement. The extended end of the shaft 71 is splined at 73 for receiving a winch or other suitable drive means for rotating the shaft and causing the casting to be drawn towards or away from each other. This produces a bowing or deflecting of the cross beam 63 towards and away from the material pass line depending on whether the arms 66 and 67 are pulled together or pushed apart by rotation of the shaft 71. The effect of the bowing of the cross beam is transmitted to the shafts 52 of the roller assemblies 48 and 49 producing a similar bowing of these roller assemblies which bowing now has the characteristics of a crown on a roll. Since the roller assemblies 48 and 49 support, in part, ultimately the upper work roll 41, the crown effect is transmitted through the intermediate backing rolls to the work roll and, thereby, effectively controls the shape of the opening between the two work rolls. After the shaft 71 is rotated to roduce the desired crown effect on the rolls, a locking pin 71a is moved into engagement with a gear wheel 71b secured on the shaft 71 to prevent further rotation of the shaft.

With reference again to FIGS. 1 and 2, there is illustrated adjustment means 74 carried in each housing for positioning the roller assemblies 48 and 49 relative to the pass line of the mill. Each adjusting means 74 comprises a spindle 75 provided at one end with gear teeth 76 that mesh with gear segments 77 and 78 secured to the shafts 52 of the roller assemblies 48 and 49. Formed to the other end of the spindle 75 is a worm gear unit 79 driven by a motor 80, shown in FIG. 3. Rotation of the spindle 75 by. the motor 80 causes rotation of the eccentric portions 52a of the shaft for the roller assemblies 48 and 49, thus displacing these roller assemblies relative to the pass line of the mill and, in effect, changing the distance between the work rolls.

With reference now to the second embodiment of the present invention, as illustrated in FIGS. and 6, there is provided a pair of spaced-apart housings 81 and 82, each having a window 83 into which there is received a pair of work rolls 84 and 85 supported in bearing chock assemblies 84a and 85a, respectively. A lower backup roll 86 has a bearing chock assembly 86a that rotatably supports the backup roll in the housing. The upper work roll 84 is supported by a backup roll assembly 87 constructed in accordance with the teachings of the present invention. The backup roll assembly 87 consists of a plurality of spaced-apart rollers 88 rotatably mounted by bearings on a shaft 89. A plurality of support members 90 are arranged along the length of the shaft 89 intermediate the rollers 88 and at each end thereof. The top portionof each support member is constructed in the shape ofa T and adapted to be slidably received in a similarly shaped slot formed in a support beam 91. The beam 91 is supported in the housings by a conventional rolling mill screwdown apparatus, which includes screws 92 threadably received in nuts 93 supported against rotation in the housings. Referring again to the beam 91, it is formed with two opposed arms 91a and 91b which project upwardly between the housings. Formed on the ends of these arms 91a and 91b are circular castings 94 and 95. These castings have internal threads that mesh with threads formed on a common shaft 96 which is held against axial movement. Secured to this shaft between the circular castings is a gear wheel 97 that meshes with a worm gear 98 driven by a motor 99.

In the operation of the crown control device according to this embodiment of the present invention, the motor 99 is actuated to rotate the shaft 96 and draw the circular castings 94 and 95 towards or away from each other, thereby imposing a bending moment on the beam 91. This results in a bowing of the beam relative to the pass line of the mill. Since the beam supports the backup roll assembly 87, the rollers thereof assume a position which now takes the form of a crown on a roll. Since the roll assembly 87 supports the work roll 84, the crowned shape of the assembly is transmitted to the work roll.

It will be appreciated by those skilled in the art that the present invention may be embodied in other rolling mill arrangements, such as a five-high or six-high arrangement of rolls. In such an arrangement one or both of the ultimate supporting roller assemblies will take the form of the roll assembly 87 illustrated in the second embodiment or the roller assembly 48 or 49 illustrated in the first embodiment.

In accordance with the provisions of the patent statutes, I have explained the principle and operation of my invention and have illustrated and described what I consider to represent the best embodiment thereof.

I claim:

1. In a multi-high rolling mill having a housing for receiving a pair of work roll assemblies and at least one backup roll assembly for supporting one of the work roll assemblies and arranged to receive at least a portion of the rolling force to which the supported work roll assembly is subject,

a beam supported by said housing and arranged in a rolling force transmitting relationship between said housing and said backup roll assembly,

means for connecting said beam to the outer ends of said backup roll assembly, and

a force generating means also connected to said beam for deflecting said beam in a direction to deflect the backup roll assembly to control the crown of said one work roll assembly.

2. In a rolling mill including a housing,

a window in said housing,

a pair of work roll assemblies received in said window between which strip-like material to be rolled is fed,

a backup roll assembly received in said window for supporting at least one of said work roll assemblies and arranged to receive at least a portion of a rolling force to which the supported work roll assembly is subject,

a deflectable beam supported by said housings and arranged in a rolling force transmitting relationship between said housing and said backup roll assembly,

means for connecting said beam to the outer ends of said backup roll assembly, and

a force generating means also connected to said beam for deflecting said beam in a manner to deflect said backup roll assembly to control the crown of said one work roll assembly,

the construction and relationship of said beam and said force generating means being such that the force of said force generating means is self-contained within said beam.

3. In a rolling mill according to claim 2 including:

two or more backup roll supporting assemblies for each work roll assembly,

intermediate roll assemblies arranged between and in engagement with said backup roll assemblies and said work roll assemblies, and

a said deflectable beam and a said force generating means for at least two backup roll assemblies.

4. In a rolling mill according to claim 3 including drive means for said intermediate roll assemblies and wherein said two backup roll assemblies comprise a plurality of casters arranged to extend along the bodies of several of said intermediate roll assemblies.

5. In a rolling mill according to claim 3 including:

other intermediate roll assemblies arranged between and in engagement with said work roll assemblies and said driven intermediate roll assemblies,

said backup roll assemblies for one of said work roll assemblies having plain roll bodies,

said backup roll assemblies for said other work roll assembly, each having a plurality of casters,

said innermost caster backup roll assemblies each carrying a deflectable beam, and

means for adjusting each of said backup roll assemblies relative to the work roll assemblies.

6. In a rolling mill according to claim 3 wherein said two backup roll assemblies that carry said deflectable beams include a plurality of casters arranged to extend along the body of said intermediate roll assemblies,

said deflectable beams comprising means for rotatably supporting said casters and including means for connecting a frame for rotatably supporting said casters and constructed to receive a portion of the rolling loads of the mill,

said beam having means for carrying said frame in a manner that the frame transfers a portion of the rolling load to the beam, and

a pair of spaced-apart screws carried by said housing engaging with said beam adapted to move the beam in said window to adjust the work rolls, said beam being arranged between said screws.

8. In a rolling mill according to claim 5 in which said beam includes a portion having opposite hand threads,

said force generating means including a shaft having opposite hand threads received by said portion,

power means for driving said shaft to cause said beam to deflect. 

1. In a multi-high rolling mill having a housing for receiving a pair of work roll assemblies and at least one backup roll assembly for supporting one of the work roll assemblies and arranged to receive at least a portion of the rolling force to which the supported work roll assembly is subject, a beam supported by said housing and arranged in a rolling force transmitting relationship between said housing and said backup roll assembly, means for connecting said beam to the outer ends of said backup roll assembly, and a force generating means also connected to said beam for deflecting said beam in a direction to deflect the backup roll assembly to control the crown of said one work roll assembly.
 2. In a rolling mill including a housing, a window in said housing, a pair of work roll assemblies received in said window between which strip-like material to be rolled is fed, a backup roll assembly received in said winDow for supporting at least one of said work roll assemblies and arranged to receive at least a portion of a rolling force to which the supported work roll assembly is subject, a deflectable beam supported by said housings and arranged in a rolling force transmitting relationship between said housing and said backup roll assembly, means for connecting said beam to the outer ends of said backup roll assembly, and a force generating means also connected to said beam for deflecting said beam in a manner to deflect said backup roll assembly to control the crown of said one work roll assembly, the construction and relationship of said beam and said force generating means being such that the force of said force generating means is self-contained within said beam.
 3. In a rolling mill according to claim 2 including: two or more backup roll supporting assemblies for each work roll assembly, intermediate roll assemblies arranged between and in engagement with said backup roll assemblies and said work roll assemblies, and a said deflectable beam and a said force generating means for at least two backup roll assemblies.
 4. In a rolling mill according to claim 3 including drive means for said intermediate roll assemblies and wherein said two backup roll assemblies comprise a plurality of casters arranged to extend along the bodies of several of said intermediate roll assemblies.
 5. In a rolling mill according to claim 3 including: other intermediate roll assemblies arranged between and in engagement with said work roll assemblies and said driven intermediate roll assemblies, said backup roll assemblies for one of said work roll assemblies having plain roll bodies, said backup roll assemblies for said other work roll assembly, each having a plurality of casters, said innermost caster backup roll assemblies each carrying a deflectable beam, and means for adjusting each of said backup roll assemblies relative to the work roll assemblies.
 6. In a rolling mill according to claim 3 wherein said two backup roll assemblies that carry said deflectable beams include a plurality of casters arranged to extend along the body of said intermediate roll assemblies, said deflectable beams comprising means for rotatably supporting said casters and including means for connecting said beams to said housing, said force generating means including separate screw assemblies adapted to impose on said beams equal and opposite forces to cause said beams to deflect in a direction to displace said casters in a manner to compensate for the deflection of the work rolls due to the rolling load.
 7. In a rolling mill according to claim 2 wherein said backup roll assembly comprises a plurality of casters arranged along the body of one of said work roll assemblies, a frame for rotatably supporting said casters and constructed to receive a portion of the rolling loads of the mill, said beam having means for carrying said frame in a manner that the frame transfers a portion of the rolling load to the beam, and a pair of spaced-apart screws carried by said housing engaging with said beam adapted to move the beam in said window to adjust the work rolls, said beam being arranged between said screws.
 8. In a rolling mill according to claim 5 in which said beam includes a portion having opposite hand threads, said force generating means including a shaft having opposite hand threads received by said portion, power means for driving said shaft to cause said beam to deflect. 